Rate Oracle - ignores configured rate_source setting, defaults to Binance

[fengtality]

Bug Description

The rate oracle is not respecting the rate_source configuration in conf_client.yml. Even when rate_source is set to gate_io, the system still attempts to fetch rates from Binance.

Steps to Reproduce

1. Set rate_source: gate_io in bots/credentials/master_account/conf_client.yml
2. Run make run
3. Observe error logs showing Binance rate source being used instead of Gate.io

Error Log

2026-02-06 07:23:17,279 - hummingbot.core.rate_oracle.sources.rate_source_base - ERROR - Unexpected error while retrieving rates from Binance. Check the log file for more info.
Traceback (most recent call last):
  File ".../hummingbot/core/rate_oracle/sources/binance_rate_source.py", line 54, in _get_binance_prices
    pairs_prices = await exchange.get_all_pairs_prices()
  ...
  File ".../hummingbot/core/web_assistant/rest_assistant.py", line 101, in execute_request_and_get_response
    raise IOError(f"Error executing request {method.name} {url}. HTTP status is {response.status}. "
OSError: Error executing request GET https://api.binance.com/api/v3/ticker/bookTicker. HTTP status is 451. Error: {
  "code": 0,
  "msg": "Service unavailable from a restricted location according to 'b. Eligibility' in https://www.binance.com/en/terms. Please contact customer service if you believe you received this message in error."
}

Expected Behavior

When rate_source: gate_io is configured, the rate oracle should use Gate.io for price fetching, not Binance.

Actual Behavior

The rate oracle ignores the rate_source configuration and defaults to using Binance, which fails with HTTP 451 for users in restricted locations.

Environment

• Running via make run
• Configuration file: bots/credentials/master_account/conf_client.yml

Additional Context

This is particularly problematic for users in regions where Binance is blocked (HTTP 451), as there's no way to switch to an alternative rate source.